煤颗粒表面形态及其对超细粉碎的影响

Appearance of Coal Particles and Its Influence on Superfine Grinding

利用扫描电镜对煤颗粒的表面形态、结构、开裂形式等进行研究。结果表明,煤颗粒的表面形态对超细粉碎过程有重要影响,颗粒表面存在的大量孔隙是开裂的起源,粗颗粒呈脆性断裂,粉碎较容易;随着颗粒的细化,开裂形式从脆性向塑性开裂转变,细颗粒煤微观断裂形态呈撕裂状,粉碎难度增大;煤超细颗粒与其它颗粒有表面和结构上的相似性,具有分形的基本特征。

The surface appearance, structure and cracking type of coal particles were studied by SEM. The coal appearance influences the superfine grinding process significantly. It was proved that there are a lot of holes and cracks on the coal surface. The holes and cracks were the source of cracking. The gain coal lumps are brittle fracture; the superfine powder fracture is laceration. The surface appearance of particles show that the grinding tape turns to plastic fracture from elastic fracture while the partr cle becoming finer. There are similarity appearance and structure among coal superfine powder and other particles with different diameter. There are basic fractal features on coal surface.